If we had UBI or something equivalent, financial literacy would probably help. But found it the other way around is simply insulting. Most poor people do not have any money to 'manage', they can only try to keep up with all expenses and hope no unexpected expenses happen. If unexpected expenses do happen, there is simply nothing good they can do about it - they must choose where to go into debt, and hope they will happen to find some way to repay that debt from an unexpected windfall.

Sure, there is a minority of cases where people squander a windfall, like in GP's example. It is such a small minority that it's barely worth mentioning.

I'd also note that people who have been toiling away for years on minimum wage may be forgiven and understood if they decide to use a small windfall on buying a small luxury like a pretty dress or trip to Disneyland for their children, instead of investing it in some stock or whatever would be the 'rational' thing to do. Humans beings are not robots, and we need more than food and a roof to live even a half-way acceptable life.